Kazakhstania Librovitch, 1940

Korn, Dieter & Weyer, Dieter, 2023, The ammonoids from the Gattendorfia Limestone of Oberrödinghausen (Early Carboniferous; Rhenish Mountains, Germany), European Journal of Taxonomy 882, pp. 1-230 : 146

Genus Kazakhstania Librovitch, 1940

Type species

Gattendorfia (Kazakhstania) karagandaensis Librovitch, 1940: 68 ; original designation.

Genus diagnosis

Genus of the Gattendorfiinae with a small, thinly discoidal to pachyconic conch with low coiling rate (WER = 1.50–1.70); all stages evolute, with depressed whorl profile. Shell surface often with constrictions on the outer flank and venter. Suture line with deep, lanceolate or slightly pouched external lobe, which is much deeper than the adventive lobe.

Genus composition

Central Europe ( Vöhringer 1960): Gattendorfia evoluta Vöhringer, 1960 .

North Africa( Bockwinkel & Ebbighausen 2006; Korn et al. 2010b): Kazakhstania nitida Bockwinkel & Ebbighausen, 2006 ; Kazakhstania inaequalis Korn, Ebbighausen, Bockwinkel, 2010 ; Kazakhstania kana sp. nov.

Central Asia ( Librovitch 1940; Kusina & Lazarev 1994; Ruan 1995): Gattendorfia (Kazakhstania) depressa Librovitch, 1940 ; Gattendorfia (Kazakhstania) karagandaensis Librovitch, 1940 ; Kazakhstania mongolica Kusina in Kusina & Lazarev, 1994; Gattendorfia (Kazakhstania) compressa Ruan, 1995 ; Gattendorfia (Kazakhstania) cuneata Ruan, 1995 ; Gattendorfia (Kazakhstania) umbilicata Ruan, 1995 .

North America ( Morton 1836; Miller & Garner 1955; Work & Mason 2005): Kazakhstania americana Miller & Garner, 1955 ; Ammonites colubrellus Morton, 1836 ; Kazakhstania mangeri Work & Mason, 2005 .

Remarks

Kazakhstania is easily distinguished from the other genera of the subfamily Gattendorfiinae because of the very wide umbilicus and the depressed whorl profile in all ontogenetic stages. Another distinguishing criterion is the very deep external lobe, which is usually one and a half to two times as deep as the adventive lobe.